GitHub User: bcardarella
It will never work with the form_tag. Sorry.
Rails 2.x is not supported in the new client_side_validations gem. The reason is because ActiveRecord 2.x does not allow reflection upon the validators. I solved this in DNC version of the gem by using a hack (validation-reflection gem) but supporting both Rails 2 & Rails 3 is very difficult so I decided to only support Rails 3.
Can you open an issue on Github? https://github.com/bcardarella/client_side_validations/issues
Thanks for the RailsCast Ryan! I encourage people to check out the wiki as there are quite a bit of different ways to customize the behavior of the validations. (callbacks, filters, etc..)
If you want to backport support for legacy browsers have a look at: https://github.com/fortes/history.js